To Place an Arc by Its Center

Select the Place Arc tool ( split button
).
 Set Method to Center, Start.

Enter a data point to define the arc's center.
If Radius, Start Angle, Direction, and either Length or Sweep Angle are all on, the arc is placed.

If necessary, enter a data point to define the arc's start point.
If Radius and Start Angle are on, this data point defines the arc's sweep angle and direction, and places the arc.
If Sweep Angle also is on, this data point defines the arc's direction and places the arc.
 If necessary, enter a data point to define the arc's sweep angle and place the arc.